Ninja School by Jakub Gruber is available at Threadless

Ninja School by Jakub Gruber is available at Threadless

The Invisible Gentleman available at Threadless

The Unseen Helpers is back in stock at Threadless

(Source: shirtoid)

The Unseen Helpers available at Threadless

Support Your Local Scientist available at SneakyStore

Invisible Giraffe available at Diesel Sweeties

Mister Invisible available at laFraise

Invisible Man available at Out of Print Clothing